This invention relates to an incandescent lamp having a light-transmitting envelope and carrying on the internal surface thereof a light diffusing coating and method for applying the coating. The prior art shows a number of compositions for the light diffusing coating as well as a number of methods for applying the same to the lamp envelope. In U.S. Pat. No. 2,545,896, issued to Pipkin is disclosed a method of applying silica to the inner surface of a lamp envelope by the process of burning organosilicates to form a fume or smoke. The resulting silica coating formed by the burning is quite inert with regard to moisture-repossessing characteristics. This process, however, is relatively expensive and does not provide a coating with light-diffusion characteristics which are as good as desired. In U.S. Pat. No. 2,661,438 issued to Shand is disclosed a process of spraying onto a heated lamp, an alkaline-reacting silica aquasol carrying large silica particles. The resulting silica coating is relatively inert to moisture. This process, though, does not provide a coating with desirable light-diffusion because of the large amounts of silica aquasols containing large silica particles that must be used. In U.S. Pat. No. 2,921,827 dated Jan. 19, 1960 issued to Meister et al and assigned to the present assignee is disclosed a method of applying a silica coating to an incandescent lamp envelope electrostatically. The electrostatic method as disclosed in the Meister patent has been found to be an excellent lamp coating process. This process gives an excellent light-diffusing coating which may be applied quickly and relatively easily. Some problems with the Meister process have been encountered in actual lamp manufacture where the silica powder used to coat the lamp contains an appreciable amount of moisture and because of maladjustments, the coating equipment has failed to remove as much of the moisture as desired. Moisture has a deleterious effect on lamp life, especially in a hot or enclosed-type fixtures where reaction with the filament can occur.